Process of preparing nitro amino benzoyl o-benzoic acid and its derivatives



Patented Jan. 18, 1927.

UNITED. STATES PATENT orrlce.

-ROGER ADAMS AND JAMES MEYER DAVIDSON, OF URBANA. ILLINOIS, AND IVAN GUBELMANN, OF SOUTH MILWAUKEE, \VISCONSIN, ASSIGNORS TO THE NEWPORT COMPANY, OF CARROLLVILLE, WISCONSIN, A CORPORATION OF DELAWARE.

PROCESS OF PREPARING NITRO AMINO BENZOYL O-BENZOIC ACID AND ITS DERIVATIVES.

Ho Drawing.

. oono, -oo

plus HNRa-a where R is a hydrogen atom, an alkyl, aryl or substituted alkyl or aryl group.

In the generalv method of synthesizing compounds of this series, the compound 4- chloro-3-nitro benzoyl o.-benzoic acid is heated alone or in a solvent with a compound of the formula HNR,, where B may represent a hydrogen atom, alkyl, aryl or substituted alkyl or aryl group. A suitable catalyst such as copper and its salts may be used .in the reaction, but it is not essential. The reacting substances are heated for several hours and the condensation product at the completion of the reaction is separated out in any of the well known ways, depending upon the character of the nitrogen compound lised. The product may be readily purified-by recrystallization from suitable organic solvents. a Without limiting our invention to any particular procedure, the following example in which parts by weight are given illustrates the application of our invention in the preferred form: I A

A mixture of parts of 4-ch1oro 3-nitro benzoyl o-benzoic acid is added to an excess of 29% aqueous ammonia to form a clear yellow solution. This mixture is then general reaction involved Application filed February 8, 1926. Serial No. 86,936.

.benzoyl o-benzoic acids. They are compounds which are soluble in alkali to give deeply colored solutions.

The following equation represents the plus H01 warmed on a water bath several hours, after "which it is diluted with water and slightly v acidified with acetic acid. The product 4:- amino 3-nitro benzoyl o-benzoic acid separates out. If desired the product may be purified from nitro benzene from which it separates as yellow crystals having a melting point when pure of from 223 to 225 C. The product obtained in the above example has the following structural formula:

the process may be varied through a wide 75 range without departing from the principles of this invention,- and we do not desire limiting the patent granted otherwise than necesstated by the prior art.

We claim asour invention:

1, The method of preparing nitro amino benzoyl o-benzoic acids of the general forin which R represents a hydrogen atom, an alkyl, aryl or substituted alkyl or aryl group, which comprises reacting upon 4-ch1oro 3- nitro benzoyl o-benzoic acid: with a compound of the formula NHR in which It may be a hydrogen atom, an alkyl, aryl or substituted alkyl or aryl group. i

2. The method of preparing 4-amino 3 nitro benzoyl o-benzoic acid, which comprises treating 4-chl0ro 3-nitro benzoyl obenzoic ac1d wlth ammonia.

3. As a new article of manufacture a compound of the general formula coon subscribed our names.

ROGER ADAMS. JAMES MEYER DAVIDSON. IVAN GUBELMANN. 

